I'm interviewing for a copywriting position tomorrow. I've been coached several times on how to interview; the best thing to do is look at the job description and come up with specific examples of how you best fit that description.
Some sample questions may be:
Tell me about a time you've had to balance multiple projects simultaneously.
Tell me about a time you've had to meet a deadline.
Questions you should always be able to answer:
Tell me a little bit about yourself (have a 30 second speech prepared).
What is your greatest strength/weakness?
What makes you the ideal candidate for this job?
Tell me about a challenge you've overcome.
And lastly, always have at least 3 questions you are prepared to ask them at the end of the interview.